a deep, hollow groan that seemed to vibrate all through the schooner.
"There—there's someone down there!" panted Bob.
"Well, what of it?" asked Frank, coolly. He did not seem nearly as frightened as were his chums.
"Then I'm not going down," went on Bob. "Maybe it's somebody hurt."
"That's all the more reason why we ought to go down—he may need help, if it's one of the sailors who couldn't get away when the others went," insisted Frank. "Come on down."
Frank's sensible talk made Bob and Sammy less afraid, and they again took their positions by their chum's side, ready to descend the companionway stairs.
Every once in a while the groan would sound again, but the boys were not so easily frightened now.
As they went down they looked about, but they saw no signs of disorder or confusion which they would have noticed had the captain and crew of the schooner left in a hurry, or after some struggle. Everything was in order, and it looked as if the sailors had just gone ashore in the regular way, leaving the vessel to the wind and sea. Before going down the boys had noticed that there were one or two small boats on the davits, showing that if the crew had left the schooner at sea, they had not taken all the rowing craft with them.
"It's a queer puzzle," said Frank, as he and his chums looked about.
"It sure is," agreed Bob. "I wonder"
"Hark!" cried Sammy.
Again came that queer, groaning sound, and it was so close at hand that the boys jumped.
"The noise came from there," said Bob, pointing to the captain's stateroom.
